@charset "UTF-8";
div {
  background: #655;
  background-image: radial-gradient(tan 30%, transparent 0), radial-gradient(tan 30%, transparent 0);
  background-size: 30px 30px;
  background-position: 0 0, 15px 15px;
}

/* 调用时是这样的…… */
.div2 {
  background: #58a;
  background-image: linear-gradient(45deg, tan 25%, transparent 0, transparent 75%, tan 0), linear-gradient(45deg, tan 25%, transparent 0, transparent 75%, tan 0);
  background-position: 0 0, 15px 15px;
  background-size: 30px 30px;
}
